Image-taking lens system

ABSTRACT

An image-taking lens system includes an image-taking lens, a lens driving control part for driving and controlling the image-taking lens, a reading part for reading information from a storage medium in which a plurality of pieces of lens control information according to conditions of shooting are stored, and a setting part for setting control parameters of the lens driving control part on the basis of the information read by the reading part. The arrangement enables the operator of the system to quickly change control characteristics for zooming and focusing as desired according to shooting conditions.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an image-taking lens systemarranged to be capable of controlling and driving movable opticalmembers provided for zooming, focusing, etc., and more particularly to abroadcasting television lens system.

[0003] 2. Description of Related Art

[0004]FIG. 5 is a block diagram showing the arrangement of theconventional TV (television) lens system. As shown in FIG. 5, in the TVlens system, an image-taking lens barrel 102 is connected to a TV camerabody 101 which is an image pickup apparatus. To the image-taking lensbarrel 102 are also connected a zooming demand part 103 and a focusingdemand part 104 which are included in an image-taking lensremote-control device. The operator of the TV lens system, such as acameraman, can perform zooming and focusing of the TV lens system byoperating the zooming demand part 103 and the focusing demand part 104so as to obtain pictures according to situations.

[0005]FIG. 6 is a block diagram showing an arrangement for control overmovable optical members such as zooming and focusing lenses in theconventional TV lens system. Referring to FIG. 6, when the operatoroperates a command member of the zooming or focusing demand part 103 or104 shown in FIG. 5, a command operation amount detecting part 106generates a command voltage 106 a according to the amount of operation.The command voltage 106 a is supplied to a command control part 107which is composed of an analog circuit, etc. The command control part107 converts the command voltage 106 a into a command voltage signal 107a which conforms to the TV lens system. The command voltage signal 107 ais inputted to the image-taking lens barrel 102.

[0006] At the image-taking lens barrel 102, the command voltage signal107 a inputted is supplied as a command value to a zooming and focusingdriving control part 110 which is composed of an analog servo circuit,etc., for zooming, focusing, etc. An output signal 110 a of the drivingcontrol part 110 is supplied to a motor arranged to actuate zooming,focusing or the like. A movable optical member 109 which is interlockedwith the motor is then moved by the motor.

[0007] With regard to driving operations for zooming and focusing in theTV lens system, it has been required that the servo characteristic andoperability of the TV lens system are arranged to be readily variableaccording to differences of shooting objects, such as drama shooting andsport relay broadcasting, etc., and also according to differences inoperating method among camera operators. For example, a drama shootingoperation to be performed within a studio requires a servocharacteristic which permits a slow and smooth zooming operation, ratherthan a speedy zooming operation, and an operability which permits easyfocusing at a focal length suited for shooting objects disposed withinthe studio.

[0008] For an outdoor shooting such as a baseball relay broadcasting, onthe other hand, a servo characteristic which permits zooming andfocusing at a maximum speed for following a fast moving object and aball and an operability which makes focusing on the infinity distanceside of the lens easier than focusing on the nearest distance side ofthe lens.

[0009] While a TV lens system is thus required to have its servocharacteristic and operability arranged to be readily variable accordingto the difference of shooting objects and the difference in liking amongoperators, the conventional TV lens system has been incapable of meetingthis requirement. Some of known focusing and zooming demand parts havebeen arranged to vary the operability of the demand part by using aselection switch 108 as shown in FIG. 6 or a volume adjuster to shiftthe constant of an analog circuit within the demand part eithercontinuously or noncontinuously in such a way as to vary a relationbetween the amount of operation and a command voltage.

[0010] However, the method for varying the operability by shifting theconstant of the analog circuit disposed within the demand part by meansof a switch or a volume adjuster to vary the command value in relationto the amount of operation has had the following shortcomings. Accordingto that method, the servo characteristic of the TV lens system remainsunchanged. Therefore, it has been impossible to improve the overalloperability including the servo characteristic. Besides, switch-over ofthe relation between the demand operation amount and the amount ofcommand by using the switch mounted on the zooming demand part or thefocusing demand part is possible only for two or three fixed patterns ofconstants set beforehand by hardware means. It is, therefore, hardlypossible to cope with all shooting situations as desired by theoperator.

[0011] Another method of continuously varying the circuit constant byusing a volume adjuster has been very troublesome, because itnecessitates frequent volume adjustment, confirmation of the result ofadjustment and repeating the adjusting operation for every shootingoperation. Besides, the demand parts permit selection of onlypredetermined relations between command amounts and command voltages.Therefore, it has been difficult for the operator to readily change theexisting setting and to store new setting as desired. Further, accordingto the prior art arrangement, items for which setting values arevariable has been limited to the operation amount and the command amountof the operation member of the zooming or focusing demand part.

[0012] Further, as related art, there is Japanese Laid-Open PatentApplication No. Hei 5-22729.

BRIEF SUMMARY OF THE INVENTION

[0013] In view of the above-stated problems of the prior art, it is anobject of the invention to provide means for varying a servocharacteristic, operability, etc., for zooming and focusing withoutdifficulty according to the shooting object and as desired by theoperator.

[0014] To attain the above object, in accordance with an aspect of theinvention, there is provided an image-taking lens system, whichcomprises an image-taking lens, lens driving control means for drivingand controlling the image-taking lens, reading means for readinginformation from a storage medium in which a plurality of pieces of lenscontrol information corresponding to conditions of shooting are stored,and setting means for setting control parameters of the lens drivingcontrol means on the basis of the information read by the reading means.The arrangement enhances, for example, servo characteristics andoperability for zooming and focusing differently required by individualshooting objects and individual operators.

[0015] In the image-taking lens system, the image-taking lens isdetachably mountable on a camera body, and the reading means is disposedat the image-taking lens.

[0016] The image-taking lens system further comprises remote operationcontrol device for remotely operating and commanding the lens drivingcontrol means. The remote operation control means includes receivingmeans for receiving information read by the reading means and permitsthe operator of the system to vary the operating characteristic of alens driving operation member according to the information received,i.e., as desired by the operator.

[0017] The image-taking lens system further comprises selection meansfor selecting necessary information from among a plurality of pieces ofinformation read by the reading means. The setting means is arranged toset control parameters of the lens driving control means according tothe information selected.

[0018] The above and further objects and aspects of the invention willbecome apparent from the following detailed description of a preferredembodiment thereof taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0019]FIG. 1 is a control block diagram showing the arrangement of a TVlens system according to an embodiment of the invention.

[0020]FIG. 2 is a perspective view showing the whole TV lens systemaccording to the embodiment.

[0021]FIG. 3 shows the appearance of a memory card unit in theembodiment.

[0022]FIG. 4 is a table showing the contents stored in a storage mediumin the embodiment.

[0023]FIG. 5 is a block diagram showing in outline the arrangement ofthe conventional TV lens system.

[0024]FIG. 6 is a control block diagram showing the arrangement forcontrol over movable optical members in the conventional TV lens system.

DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, a preferred embodiment of the invention will bedescribed in detail with reference to the drawings.

[0026]FIG. 1 is a block diagram showing the arrangement for control overmovable optical members such as zooming and focusing lenses of a TV lenssystem according to the embodiment of the invention. FIG. 2 is aperspective view showing the appearance of the TV lens system.

[0027] Referring to FIG. 1, an external storage medium C is a cardmemory or the like arranged to store contents which will be describedlater herein. An image-taking lens barrel 40 includes a zooming part, afocusing part and a control circuit and is arranged to be mounted on acamera body which is not shown.

[0028] An image-taking lens remote-control device 50 comprises a zoomdemand part 50 a and a focusing demand part 50 b as shown in FIG. 2.

[0029] Referring to FIG. 2, a memory card unit 20 is arranged to readinformation from the external storage medium C and make a display of theinformation read, and has a selection switch for performing controlaccording to conditions of shooting. The memory card unit 20 will bedescribed in detail later herein with reference to FIG. 3.

[0030] A TV lens control part 30 shown in FIG. 2 is arranged to performdriving control for zooming, focusing, etc., and to control otheractions of the TV lens system.

[0031] The contents stored in the external storage medium C is nextdescribed briefly with reference to FIG. 4. FIG. 4 shows, by way ofexample, information set within one sheet of card type storage medium.

[0032] Referring to FIG. 4, one sheet of card type storage medium iscapable of storing a total of eight data sets, which are indicated asdata sets 1 to 8. The data sets 1 to 8 respectively correspond to aplurality of shooting conditions, such as outdoor shooting, dramashooting, a studio shooting, etc. The outdoor shooting includes a sportshooting, landscape shooting, etc. The cameraman or camera operator isexpected to select an applicable and appropriate number of data setaccording to the conditions of shooting.

[0033] Further, as shown in FIG. 4, one data set has a plurality ofsetting items. For example, there are two setting items relative to azoom driving control, two setting items relative to a focus drivingcontrol, one item relative to setting a driving method either singly forzooming or focusing or for zooming and focusing in combination, twoitems relative to setting zoom demanding command control, two itemsrelative to setting focus demanding command control, and a plurality ofitems relative to other control setting. For each of setting items, oneof a plurality of setting values is set. Such information (settingparameters) is stored in the storage medium. The operator is allowed toselect or set the pieces of information as desired.

[0034] More specifically, with respect to the setting items relative tozoom driving control among other items, a zooming speed (a maximumzooming speed, for example), a rise or fall characteristic responsive toa zoom command relative to the lens moving speed, etc., are set in thefirst place. As for the setting items relative to focusing drivingcontrol, a focusing speed (a maximum focusing speed, for example) and adegree of precision of stopping position for the focusing lens are set.In respect to the setting items relative to the zoom demanding commandcontrol, a response characteristic to a zooming operation performed bythe operator, such as setting operation sensitivity, etc., are set.These setting items are stored in the storage medium to allow theoperator to select them as necessary.

[0035] In other words, the operator is allowed to make lens operationsetting as desired according to his or her own liking. Zoom and focusingservo characteristics, zoom and focusing demand operationcharacteristics, etc., are variable as desired by selecting desiredsetting items and desired setting values according to the conditions ofshooting. The embodiment thus enables the operator to selectively obtaincharacteristics in innumerable variety.

[0036] The control arrangement shown in FIG. 1 performs control on thebasis of the information stored in the above-stated manner. Referringagain to FIG. 1, an external storage medium reading-and-recording means4 is arranged to read and record from and into the external storagemedium C the above-stated setting information such as control parametersrelative to control actions to be carried out by the image-taking lensbarrel 40 and the image-taking lens remote-control device 50.

[0037] A setting control means 5 is arranged such that, in a case wherethe setting information read out by the external storage mediumreading-and-recording means 4 relates, for example, to driving controlover the movable optical members such as the zooming or the focusinglens, the setting control means 5 changes driving control parameters ofvaried kinds (computing coefficients) of a driving control part 6according to the applicable setting item. If the setting informationrelates to the image-taking lens remote-control device 50, the settingcontrol means 5 transmits the setting information to a signal receivingmeans 11 which is disposed within the image-taking lens remote-controldevice 50.

[0038] The driving control part 6 which is provided for zooming,focusing, etc., is arranged to output a driving signal 16 for driving azooming or focusing motor on the basis of control parameters which arechanged by the setting control means 5 for driving control over zoomingor focusing and a command signal 17 which is received from a commandoutput control part 13 disposed within the image-taking lensremote-control device 50.

[0039] A driving mechanism 7 includes motors for driving focusing andzooming lenses and potentiometers and rotary encoders for positiondetection. The driving mechanism 7 is arranged to optically change thepositions of zooming and focusing on the basis of the signal receivedfrom the driving control part 6 for zooming and focusing.

[0040] A selection means 8 is arranged to select information from amongsetting information of varied kinds read out from the external storagemedium C by the external storage medium reading-and-recording means 4.In a case where setting information retained within the image-takinglens barrel 40 or within the image-taking lens remote-control device 50is to be recorded on the external storage medium C, the selection means8 selects information to be recorded from among the setting informationof different kinds.

[0041] A display means 9 is arranged to enable the operator to know thestate of the setting information, etc. An editing means 10 is arrangedto read a plurality of pieces of setting information from a single or aplurality of external storage media C through the external storagemedium reading-and-recording means 4 and to permit preparation of a newcombination of pieces of setting information.

[0042] The image-taking lens remote-control device 50 includes thesignal receiving means 11 which is arranged to receive, from the settingcontrol means 5 of the image-taking lens barrel 40, setting informationto be changed on the side of the image-taking lens remote-control device50. A setting control means 12 which is disposed on the side of theimage-taking lens remote-control device 50 is arranged to set variousmatters within the image-taking lens remote-control device 50 on thebasis of setting information of varied kinds obtained through the signalreceiving means 11 and also information coming from a selection switch15 which is provided on the side of the image-taking lens remote-controldevice 50.

[0043] In a case where the setting information includes, for example,information relative to command control, the setting control means 12set parameters, etc., related to command control at the command outputcontrol part 13. A command operation amount detecting part 14 isarranged to output an operation command 18 in proportion to the amountof operation when the operator, or cameraman, performs a zooming orfocusing operation. The command output control part 13 is arranged toform the command signal 17 to be applied to the image-taking lens barrel40 according to the operation command 18 coming from the commandoperation amount detecting part 14 and on the basis of the parametersrelative to command control set by the setting control means 12 withinthe image-taking lens remote-control device 50.

[0044] In the arrangement described above, it is now assumed that, withrespect to driving control over zooming, focusing, etc., of the TV lenssystem, there are a first external storage medium and a second externalstorage medium; the first external storage medium (a master card)storing all setting values of zooming and focusing control of the TVlens system to cover zooming and focusing demands according toimage-taking conditions, and the second external storage medium beingindividually possessed by the operator.

[0045] The operator first connects the first external storage medium tothe external storage medium reading-and-recording means 4. After that,the operator selects a desired combination of setting values by theselection means 8 while looking at the display means 9. The settingvalues of varied kinds thus selected are read by the external storagereading-and-recording means 4. The setting control means 5 then changesvarious driving control parameters of the driving control part 6 forzooming, focusing, etc., according to the setting values read by theexternal storage reading-and-recording means 4.

[0046] If the setting values selected include setting values related tothe image-taking lens remote-control device 50, the setting controlmeans 5 of the image-taking lens barrel 40 sends the setting values ofvaried kinds to the setting control means 12 disposed within theimage-taking lens remote-control device 50 through the signal receivingmeans 11 which is also disposed within the image-taking lensremote-control device 50.

[0047] Upon receipt of the various setting values from the settingcontrol means 5 of the image-taking lens barrel 40 through the signalreceiving means 11, the setting control means 12 of the image-takinglens remote-control device 50 decides parameters, etc., for commandcontrol according to the various setting values inputted and the stateof the selection switch 15 mounted on the image-taking lensremote-control device 50 and sets the decided command control parametersat the command output control part 13. At the command output controlpart 13, the operation command 18 received from the command operationamount detecting part 14 is converted into the command signal 17 on thebasis of the setting values set by the setting control means 12. Thecommand signal 17 is sent out to the image-taking lens barrel 40.

[0048] The use of the first external storage medium thus enables theoperator to easily change the various control parameters of theimage-taking lens barrel 40 and those of the image-taking lensremote-control device 50. In respect of driving control for zooming andfocusing, for example, the conventional arrangement allows the operatorto change the operation characteristics of zooming and focusing demandsonly to a slight extent by means of a switch or a volume adjusting part.The arrangement of the embodiment of the invention described, on theother hand, enables the operator to change a zooming servocharacteristic, a focusing servo characteristic, a zooming demandoperation characteristic, a focusing demand operation characteristic,etc., into any of almost innumerable characteristics as desired, byusing setting values of a plurality of setting items according to theshooting conditions, etc.

[0049] After completion of the above-stated operation of selectivesetting information reading from the first external storage medium, thesecond external storage medium which is individually or personallypossessed by the operator may be connected to the external storagemedium reading-and-recording means 4. With the second external storagemedium thus connected, the setting information obtained from the firstexternal storage medium can be recorded on the second external storagemedium by carrying out a recording operation on the second externalstorage medium. In this instance, the information to be recorded on thesecond external storage medium can be selected as desired by theselection means 8.

[0050] Further, a plurality of external storage media which have beenset similarly to the first external storage medium may be seriallyconnected to the external storage reading-and-recording means 4 oneafter another by the editing means 10. After that, by connecting thesecond external storage medium to the external storagereading-and-recording means 4 and by carrying out a recording operation,it is possible to selectively collect only necessary setting valueseither from one or a plurality of external storage media and to recordthe selected setting values in one of the external storage media byoperating the editing means 10. In that instance, the operator caneasily arrange the TV lens system according to the operator's ownliking.

[0051]FIG. 3 shows in detail the arrangement of the memory card unit 20.Referring to FIG. 3, a card type storage medium C is arranged to permitreading therefrom and writing therein the above-stated settinginformation of varied kinds and to be detachably mountable on the memorycard unit 20. A storage medium mounting indicator 22 is arranged to showwhether or not the card type storage medium C is correctly mounted onthe memory card unit 20. An error indicator 23 is arranged to show thatthe card type storage medium C is not normally handled. A data-set/itemselecting switch 24 is provided for selection of a mode of selectingdata sets previously selected or a mode of switching items within thedata sets.

[0052] Selection switches 25 and 26 are arranged to permit selection ofa data set or an item in the data set mode or in the item mode selectedby the data-set/item selecting switch 24. A data set number indicator 27is arranged to show the number assigned to a data set currentlyselected. An item indicator 28 is arranged to show a setting itemcurrently selected.

[0053] An execution switch 29 is provided for reading out from the cardtype storage medium C one or a plurality of items within one data setselected by the data-set/item selection switch 24 and the selectionswitch 25 or 26 and for carrying out a changing action on one or aplurality of setting values of the image-taking lens barrel 40 and theimage-taking lens remote-control device 50 on the basis of the settingvalue or values read out. A reading switch 30 is provided for readingout from the card type storage medium C one or a plurality of itemswithin one data set selected by the data-set/item selection switch 24and the selection switch 25 or 26 and for causing the information readout to be stored within the image-taking lens barrel 40 or theimage-taking lens remote-control device 50.

[0054] A writing switch 31 is provided for carrying out a rewritingaction to replace one of or a plurality of items selected from among thesetting values of varied kinds stored within the image-taking lensbarrel 40 or the image-taking lens remote-control device 50 by thedata-set/item selection switch 24 and the selection switch 25 or 26 withone or a plurality of items selected from one data set stored in thecard type storage medium C also by the data-set/item selection switch 24and the selection switch 25 or 26.

[0055] An execution indicator 32 is arranged to show that theimage-taking lens barrel 40 and the image-taking lens remote-controldevice 50 are in action on the basis of the setting values which areread out from the card type storage medium C by the execution switch 29.A reading indicator 33 is arranged to show that setting informationwhich is read out from the card type storage medium C by the readingswitch 30 is stored in the image-raking lens barrel 40 and theimage-taking lens remote-control device 50. A writing indicator 34 isarranged to show that a setting item designated is written from theimage-taking lens barrel 40 into the card type storage medium C by thewriting switch 31.

[0056] With the memory card unit 20 shown in FIG. 3 arranged asdescribed above, the card type storage medium C which has already beenset is first mounted on the memory card unit 20. When the card typestorage medium C is found to be correctly mounted, the storage mediummounting indicator 22 either lights up or flickers to let the operatorknow that the card type storage medium C is correctly mounted. If thecard type storage medium C is found to be not correctly mounted, theerror indicator 23 either lights up or flickers.

[0057] When the storage medium mounting indicator 22 lights up orflickers to show that the card type storage medium C is correctlymounted, the operator operates the data-set/item selection switch 24 andthe selection switches 25 and 26 to select a data set and one or aplurality of items desired to be set in the image-taking lens barrel 40and the image-taking lens remove control device 50 while watching thedata set number indicator 27 and the item indicator 28 for confirmation.

[0058] Next, to decide what is to be done for the data set and the itemselected, the operator pushes the execution switch 29, the readingswitch 30 or the writing switch 31. When the execution switch 29 ispushed, the selected item of a data set previously selected is read outfrom the card type storage medium C and is executed. The executionindicator 32 then lights up or flickers.

[0059] When the reading switch 30 is pushed, the selected item of a dataset previously selected is read out from the card type storage medium Cand written into the image-taking lens barrel 40 or the image-takinglens remote-control device 50. The reading indicator 33 then lights upor flickers. If it is the writing switch 30 that is pushed, the selecteditem of the previously selected data set is written from theimage-taking lens barrel 40 or the image-taking lens remote-controldevice 50 into the card type storage medium C.

[0060] Further, it is possible to operate the reading switch 30 to readthe setting value of each setting item from the card type storage mediumC in which one or a plurality of setting values of varied kinds arestored, to prepare a new combination of setting values, and to form thenew combination of setting values as one data set within a card typestorage medium by operating the writing switch 31.

[0061] In the embodiment described above, an external storage readingdevice (the external storage medium reading-and-recording means 4) isdisposed in the image-taking lens barrel 40. However, the externalstorage reading device may be disposed in the image-taking lensremote-control device, instead of the image-taking lens barrel. In thecase of that modification, the signal receiving means 11 is disposed onthe side of the image-taking lens barrel.

[0062] As described above, the image-taking lens system arrangedaccording to the invention comprises the external storage mediumrecording-and-writing means, the setting control means, the signalreceiving means, the display means, the editing means and the selectionmeans. The arrangement facilitates various setting operations on theimage-taking lens system by using an external storage medium which hasalready been set and allows the operator to arrange the image-takinglens system according to shooting conditions. Further, selectively setcontents (setting values) of the system can be stored in a portablestorage medium, so that the same image-taking lens system can bereproduced any time later on. In other words, the operator (cameraman)can readily form an image-taking lens system as desired according to anyshooting conditions.

1. An image-taking lens system comprising: an image-taking lens; lensdriving control means for driving and controlling said image-takinglens; reading means for reading information from a storage medium inwhich a plurality of pieces of lens control information corresponding toconditions of shooting are stored; and setting means for setting controlparameters of said lens driving control means on the basis of theinformation read by said reading means.
 2. An image-taking lens systemaccording to claim 1, wherein said image-taking lens is detachablymountable on a camera body, and said reading means is disposed at saidimage-taking lens.
 3. An image-taking lens system according to claim 1,further comprising a remote operation control device for remotelycommanding and operating said lens driving control means, said remoteoperation control device having receiving means for receiving theinformation read by said reading means.
 4. An image-taking lens systemaccording to claim 1, further comprising selection means for selectingnecessary information from among a plurality of pieces of informationread by said reading means, and wherein said setting means sets controlparameters of said lens driving control means according to theinformation selected by said selection means.
 5. An image-taking lenssystem according to claim 3, wherein said reading means is disposed atsaid remote operation control device.